Towing Couplers of a Multilink Traverser

Abstract

It is known that the toughest stage of operation of a tractor with massive towed objects is the takeoff regime. This is because it is necessary to overcome the force of friction of rest that substantially exceeds the force of friction of motion. As a variant of solution of this problem, the initial kinetic energy of the tractor can be considered, which can evolve when boundedly elastically deformed towing couplers are used. To optimize the mathematical model, the following assumptions are made: towing force \(F\) at the hook of the tractor is an invariable quantity; the inert masses of the tractor and towed objects are identical and equal to \(m\). The initial conditions are as follows: \({{{{d}^{2}}{{x}_{2}}} \mathord{\left/ {\vphantom {{{{d}^{2}}{{x}_{2}}} {d{{t}^{2}}}}} \right. \kern-0em} {d{{t}^{2}}}} = z = 0\) for t = 0 because the towing coupler is undeformed, and no force is applied to the towed object. Period \({{\tau }_{2}}\) during which the towing coupler experiences the maximal strain is determined. For estimating the effectiveness of application of elastically deformed towing couplers, the obtained results must be compared with analogous results corresponding to absolutely rigid towing couplers. Comparison of displacements, velocities, and energies indicates the high efficiency of application of elastically deformed towing coupler. The use of elastically deformed towing couplers makes it possible to accumulate the initial kinetic energy of an airport tractor, which makes it possible to overcome the force of friction of rest and to ensure the takeoff of heavy objects being towed. Comparison of kinematic and dynamic parameters of the tractor and towed objects in variants with absolutely rigid and elastically deformed towing couplers shows that the efficiency for the latter variant increases with increasing number of towed objects. Elastically deformed towing couplers can cause vibrations of the tractor–towed object system. To prevent such vibrations, towing couplers should be blocked at the instant of their highest straining.